Mayonnaise is a thick, viscous, non-pourable food dressing which has achieved great popularity for use in a variety of salads containing vegetables, meat, or seafood. The regulations of the Food and Drug Administration state that mayonnaise must contain vegetable oil, acidifying ingredients, egg yolk-containing ingredients, and, optionally, any number of spices, preservatives, or crystallization inhibitors. The oil content in mayonnaise must be not less than 65 wt. %.
The egg yolk in mayonnaise has a significant role, because it imparts a desirable flavor and functions as an emulsifier. Nevertheless, egg yolk possesses two serious drawbacks relating to consumer usage and storage.
One problem with egg yolk is that it has a very high cholesterol level. Medical authorities have determined that humans having a high level of cholesterol in their blood are susceptible to heart attacks. To avoid the risk of heart disease, many, especially those with high blood cholesterol levels, have reduced their consumption of products containing high levels of cholesterol, including egg yolk. Accordingly, the reduction of egg yolk from mayonnaise to reduce its cholesterol content would be highly desirable.
Egg yolk also may reduce the period mayonnaise can be stored due to the susceptibility of egg to microbiological spoilage. More particularly, egg yolk may contain certain microorganisms prior to its use in mayonnaise which may ultimately contaminate the entire mayonnaise product, especially after the consumer has opened it. Mayonnaise, therefore, generally may have a shortened shelf life. The elimination of egg yolk from mayonnaise-type products would, therefore, benefit that product's storage capability.
Although a number of mayonnaise substitutes have been developed, all have serious deficiencies.
One approach has been to replace egg yolk with a starch paste for thickening and edible gums for emulsification, as suggested by U.S. Pat. No. 3,764,347 to Katz ("Katz"). U.S. Pat. No. 3,692,543 to Powell, U.S. Pat. No. 4,059,458 to Germino et al., and U.S. Pat. No. 4,562,086 to Smolka also suggest the use of starches in salad dressings or mayonnaise to reduce or eliminate the quantity of egg yolk utilized. The use of a starch paste, however, requires an increase in the extent and cost of processing and tends to affect adversely the texture of the mayonnaise substitute. Moreover, the combination of starch paste and edible gums cannot maintain a stable oil-in-water emulsion at the high oil levels usually present in real mayonnaise. This high level of oil in real mayonnaise makes its oil-in-water emulsion susceptible to breaking, and the problem becomes more pronounced when starch paste and edible gums are used instead of egg yolk. As a result, the oil content of mayonnaise substitutes with these ingredients must be reduced to maintain stability. This change in oil content further adversely affects the flavor and texture of the mayonnaise substitute compared to real mayonnaise. In effect, such mayonnaise substitutes (rather than being like real mayonnaise) assume the characteristics of a salad dressing, which, under FDA standards, are permitted to use starch paste and have oil contents as low as 30%.
Another approach to preparing low cholesterol, dressing-type products, including mayonnaise, is to replace the egg yolk with a proteinaceous emulsifier. Examples of such mayonnaise substitutes are disclosed by U.S. Pat. No. 4,293,574 to Mikami et al., U.S. Pat. No. 4,304,795 to Takada et al., U.S. Pat. No. 3,892,873 to Kolen et al. ("Kolen"), Japanese Patent Application No. 57-186,463, and Japanese Patent Application No. 57-105,159. Generally, however, such formulations also have a relatively low oil level which causes them to differ in texture and flavor from real mayonnaise. Kolen suggests using higher oil levels, but the use of its proteinaceous emulsifier is expensive, because a serum protein derived from milk is utilized which must undergo heat processing to achieve a particular level of denaturation. Further, once this denaturation level is achieved, special handling and drying techniques are required to maintain that level.